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  • 1.
    Akner-Koler, Cheryl
    et al.
    Industridesignprogrammet, Konstfack, Stockholm, Sweden.
    Ranjbar, Parivash
    Örebro University Hospital. Örebro University, School of Health Sciences. Institutionen för naturvetenskap och teknik, School of Science and Technology, Örebro University, Örebro, Sweden.
    Integrating Sensitizing Labs in an Educational Design Process for Haptic Interaction2016In: FORMakademisk, ISSN 1890-9515, E-ISSN 1890-9515, Vol. 9, no 2, p. 1-25Article in journal (Refereed)
    Abstract [en]

    New design methods for educating designers are needed to adapt the attributes of haptic interaction to fit the embodied experience of the users. This paper presents educationally framed aesthetic sensitizing labs: 1) a material-lab exploring the tactile and haptic structures of materials, 2) a vibrotactile-lab exploring actuators directly on the body and 3) a combined materials- and vibrotactile-lab embedded in materials. These labs were integrated in a design course that supports a non-linear design process for embodied explorative and experimental activities that feed into an emerging gestalt. A co-design process was developed in collaboration with researchers and users who developed positioning and communications systems for people with deafblindness. Conclusion: the labs helped to discern attributes of haptic interactions which supported designing scenarios and prototypes showing novel ways to understand and shape haptic interaction.

  • 2.
    Larsson, Matz
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital. Cardiology-Lung Clinic, Örebro University Hospital, Örebro, Sweden; Institute of Environmental Medicine, Karolinska Institutet, Sweden.
    Ekström, Seth Reino
    Audiological Research Center, Ahlsén's Research Institute, Örebro, Sweden.
    Ranjbar, Parivash
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Audiological Research Center, Ahlsén's Research Institute, Örebro, Sweden.
    Effects of sounds of locomotion on speech perception2015In: Noise & Health, ISSN 1463-1741, E-ISSN 1998-4030, Vol. 17, no 77, p. 227-232Article in journal (Refereed)
    Abstract [en]

    Human locomotion typically creates noise, a possible consequence of which is the masking of sound signals originating in the surroundings. When walking side by side, people often subconsciously synchronize their steps. The neurophysiological and evolutionary background of this behavior is unclear. The present study investigated the potential of sound created by walking to mask perception of speech and compared the masking produced by walking in step with that produced by unsynchronized walking. The masking sound (footsteps on gravel) and the target sound (speech) were presented through the same speaker to 15 normal-hearing subjects. The original recorded walking sound was modified to mimic the sound of two individuals walking in pace or walking out of synchrony. The participants were instructed to adjust the sound level of the target sound until they could just comprehend the speech signal ("just follow conversation" or JFC level) when presented simultaneously with synchronized or unsynchronized walking sound at 40 dBA, 50 dBA, 60 dBA, or 70 dBA. Synchronized walking sounds produced slightly less masking of speech than did unsynchronized sound. The median JFC threshold in the synchronized condition was 38.5 dBA, while the corresponding value for the unsynchronized condition was 41.2 dBA. Combined results at all sound pressure levels showed an improvement in the signal-to-noise ratio (SNR) for synchronized footsteps; the median difference was 2.7 dB and the mean difference was 1.2 dB [P < 0.001, repeated-measures analysis of variance (RM-ANOVA)]. The difference was significant for masker levels of 50 dBA and 60 dBA, but not for 40 dBA or 70 dBA. This study provides evidence that synchronized walking may reduce the masking potential of footsteps.

  • 3.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Omgivningens ljud fångas upp av nytt hjälpmedel2010In: AudioNYTT, ISSN 0347-6308, Vol. 37, no 4, p. 14-17Article in journal (Other academic)
  • 4.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Sensing the Environment: a Perceptual and Psychosocial Analysis of Events in the Surroundings from a Handicap Perspective. Medicinteknikdagarna Örebro2007Conference paper (Refereed)
  • 5.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Sensing the Environment: a Perceptual and Psychosocial Analysis of Events in the Surroundings from a Handicap Perspective. Missisauga2003Conference paper (Other academic)
  • 6.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Sensing the Environment: a Perceptual and Psychosocial Analysis of Events in the Surroundings from a Handicap Perspective. Perth2007Conference paper (Other academic)
  • 7.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Sensing the environment: development of monitoring aids for persons with profound deafness or deafblindness2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Earlier studies of persons with deafness (D) and/or deafblindness (DB) have primarily focused on the mobility and communication problems. The purpose of the present study was to develop technology for monitoring aids to improve the ability of persons with D and/or DB to detect, identify, and perceive direction of events that produce sounds in their surroundings.

    The purpose was achieved stepwise in four studies. In Study I, the focus was on hearing aids for persons with residual low frequency hearing. In Study II-IV, the focus was on vibratory aids for persons with total D.

    In Study I, six signal processing algorithms (calculation methods) based on two principles, transposition and modulation, were developed and evaluated regarding auditory identification of environmental sounds. Twenty persons with normal hearing listened to 45 environmental sounds processed with the six different algorithms and identified them in three experiments. In Exp. 1, the sounds were unknown and the subjects had to identify them freely. In Exp. 2 and 3, the sounds were known and the subjects had to identify them by choosing one of 45 sounds. The transposing algorithms showed better results (median value in Exp. 3, 64%-69%) than the modulating algorithms (40%-52%) did, and they were good candidates for implementing in a hearing aid for persons with residual low frequency hearing.

    In Study II, eight algorithms were developed based on three principles, transposition, modulation, and filtration – in addition to No Processing as reference, and evaluated for vibratory identification of environmental sounds. The transposing algorithms and the modulating algorithms were also adapted to the vibratory thresholds of the skin. Nineteen persons with profound D tested the algorithms using a stationary, wideband vibrator and identified them by choosing one of 10 randomly selected from the list of 45 sounds. One transposing algorithm and two modulating algorithms showed better (p<0.05) scores than did the No Processing method. Two transposing and three modulating algorithms showed better (p<0.05) scores than did the filtering algorithm. Adaptation to the vibratory thresholds of the skin did not improve the vibratory identification results.

    In Study III, the two transposing algorithms and the three modulating algorithms with the best identification scores in Study II, plus their adapted alternative, were evaluated in a laboratory study. Five persons from Study II with profound D tested the algorithms using a portable narrowband vibrator and identified the sounds by choosing one of 45 sounds in three experiments (Exp. 1, 2, and 3). In Exp. 1, the sounds were pre-processed and directly fed to the vibrator. In Exp. 2 and 3, the sounds were presented in an acoustic test room, without or with background noise (SNR=+5 dB), and processed in real time. Five of the algorithms had acceptable results (27%-41%) in the three experiments and constitute candidates for a miniaturized vibratory aid (VA). The algorithms had the same rank order in both tests in the acoustic room (Exp. 2, and 3), and the noise did not worsen the identification results.

    In Study IV, the portable vibrotactile monitoring aid (with stationary processor) for detection, identification and directional perception of environmental sounds was evaluated in a field study. The same five persons with profound D as in Study III tested the aid using a randomly chosen algorithm, drawn from the five with the best results in Study III, in a home and in a traffic environment. The persons identified 12 events at home and five events in a traffic environment when they were inexperienced (the events were unknown) and later when they were experienced (the events were known). The VA consistently improved the ability with regard to detection, identification and directional perception of environmental sounds for all five persons.

    It is concluded that the selected algorithms improve the ability to detect, and identify sound emitting events. In future, the algorithms will be implemented in a low frequency hearing aid for persons with low frequency residual hearing or in a fully portable vibratory monitoring aid, for persons with profound D or DB to improve their ability to sense the environment.

    List of papers
    1. Auditive identification of signal-processed environmental sounds: monitoring the environment
    Open this publication in new window or tab >>Auditive identification of signal-processed environmental sounds: monitoring the environment
    2008 (English)In: International Journal of Audiology, ISSN 1499-2027, E-ISSN 1708-8186, Vol. 47, no 12, p. 724-736Article in journal (Refereed) Published
    Abstract [en]

    The goal of the present study was to compare six transposing signal-processing algorithms based on different principles (Fourier-based and modulation based), and to choose the algorithm that best enables identification of environmental sounds, i.e. improves the ability to monitor events in the surroundings. Ten children (12-15 years) and 10 adults (21-33 years) with normal hearing listened to 45 representative environmental (events) sounds processed using the six algorithms, and identified them in three different listening experiments involving an increasing degree of experience. The sounds were selected based on their importance for normal hearing and deaf-blind subjects. Results showed that the algorithm based on transposition of 1/3 octaves (fixed frequencies) with large bandwidth was better (p<0.015) than algorithms based on modulation. There was also a significant effect of experience (p<0.001). Adults were significantly (p<0.05) better than children for two algorithms. No clear gender difference was observed. It is concluded that the algorithm based on transposition with large bandwidth and fixed frequencies is the most promising for development of hearing aids to monitor environmental sounds.

    Place, publisher, year, edition, pages
    London: Taylor & Francis, 2008
    National Category
    Electrical Engineering, Electronic Engineering, Information Engineering Medical Engineering
    Research subject
    Medicine; Electrical Engineering
    Identifiers
    urn:nbn:se:oru:diva-6995 (URN)10.1080/14992020802289776 (DOI)19085397 (PubMedID)
    Available from: 2009-05-28 Created: 2009-05-28 Last updated: 2018-10-31Bibliographically approved
    2. Vibrotactile identification of signal-processed sounds from environmental events
    Open this publication in new window or tab >>Vibrotactile identification of signal-processed sounds from environmental events
    2009 (English)In: Journal of rehabilitation research and development, ISSN 0748-7711, E-ISSN 1938-1352, Vol. 46, no 8, p. 1021-1036Article in journal (Refereed) Published
    Abstract [en]

    Objective: To compare three different signal-processing principles (eight basic algorithms), transposing, modulating and filtering, and to find the principle(s)/al­go­rithm(s) that result in the best tactile identification of environmental sounds.

    Subjects: Nineteen volunteers (9F/10M), deaf or profoundly hearing impaired, between 18-50 yr. 

    Method: Sounds produced by 45 representative en­vi­ron­men­tal events were processed using the different al­go­rithms and presented to subjects as tactile stimuli using a wide-band stationary vibrator. Eight algorithms based on the three principles (one un­pro­cessed, used as reference) were compared. The subjects iden­ti­fied the sti­mu­li by choo­sing one among ten alter­na­tives drawn from the 45 events. 

    Result and conclusion: Algorithm and subject were significant (RM-ANOVA, p<0.001) factors affecting the results. There were also large differences between individuals regarding which algorithm was best. The test-retest variability was small (Mean±95%CI: 8±3 percentage units), and no correlation between identification score and individual vibratory thresholds was found. One transposing al­go­rithm and two mo­du­lating al­go­rithms led to significantly (p<0.05) better results than did the unprocessed signals. Thus, the two principles of transposing and modulating were appropriate, whereas filtering was unsuccessful. In future work, the two transposing algorithms and the modulating algorithms will be used in tests with a portable vibra­tor for the deafblind.

    Keywords
    Deafblind, Environmental sound, Identification, Monitoring, Perception, Tactile, Transposing, Vibration
    National Category
    Signal Processing
    Research subject
    Electronics
    Identifiers
    urn:nbn:se:oru:diva-8126 (URN)10.1682/JRRD.2008.11.0150 (DOI)000274171000005 ()20157859 (PubMedID)2-s2.0-75749141318 (Scopus ID)
    Projects
    Sensing the environment
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2018-10-31Bibliographically approved
    3. Vibrotactile identification of signal-processed sounds from environmental events presented by a portable vibrator: a laboratory study
    Open this publication in new window or tab >>Vibrotactile identification of signal-processed sounds from environmental events presented by a portable vibrator: a laboratory study
    2009 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Objective: To evaluate different signal-processing algorithms for tactile identification of environmental sounds in a monitoring aid for the deafblind.

    Subjects: Two men and three women, sensorineurally deaf or profoundly hearing impaired with experience of vibratory experiments, age 22-36 years.

    Method: A closed set of 45 representative environmental sounds were processed using two transposing (TRHA, TR1/3) and three modulating algorithms (AM, AMFM, AMMC) and presented as tactile stimuli using a portable vibrator in three experiments. The algorithms TRHA, TR1/3, AMFM and AMMC had two alternatives (with and without adaption to vibratory thresholds). In Exp. 1, the sounds were preprocessed and directly fed to the vibrator. In Exp. 2 and 3, the sounds were presented in an acoustic test room, without or with background noise (SNR=+5 dB), and processed in real time.

    Results: In Exp. 1, Algorithm AMFM and AMFM(A) consistently had the lowest identification scores, and were thus excluded in Exp. 2 and 3. TRHA, AM, AMMC, and AMMC(A) showed comparable identification scores (30%-42%) and the addition of noise did not deteriorate the performance.

    Conclusion: Algorithm TRHA, AM, AMMC, and AMMC(A) showed good performance in all three experiments and were robust in noise; they can therefore be used in further testing in real environments.

    Keywords
    Environmental sound, Identification, Narrow-band, Tactile perception, Transposing, Vibration, Vibrator
    National Category
    Signal Processing Engineering and Technology Computer and Information Sciences
    Research subject
    Signal Processing
    Identifiers
    urn:nbn:se:oru:diva-8129 (URN)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2018-01-13Bibliographically approved
    4. Vibrotactile detection, identification and directional perception of signal-processed sounds from environmental events: a pilot field evaluation in five cases
    Open this publication in new window or tab >>Vibrotactile detection, identification and directional perception of signal-processed sounds from environmental events: a pilot field evaluation in five cases
    Show others...
    2009 (English)In: Iranian Rehabilitation Journal, ISSN 1735-3602, Vol. 6, no 7-8, p. 89-107Article in journal (Refereed) Published
    Abstract [en]

    Objective: Conducting field tests of a vibrotactile aid for deaf/deafblind persons for detection, identification and directional perception of environmental sounds.

    Method: Five deaf (3F/2M, 22–36 years) individuals tested the aid separately in a home environment (kitchen) and in a traffic environment. Their eyes were blindfolded and they wore a headband and holding a vibrator for sound identification. In the headband, three microphones were mounted and two vibrators for signalling direction of the sound source. The sounds originated from events typical for the home environment and traffic. The subjects were inexperienced (events unknown) and experienced (events known). They identified the events in a home and traffic environment, but perceived sound source direction only in traffic.

    Results: The detection scores were higher than 98% both in the home and in the traffic environment. In the home environment, identification scores varied between 25%-58% when the subjects were inexperienced and between 33%-83% when they were experienced. In traffic, identification scores varied between 20%-40% when the subjects were inexperienced and between 22%-56% when they were experienced. The directional perception scores varied between 30%-60% when inexperienced and between 61%-83% when experienced.

    Conclusion: The vibratory aid consistently improved all participants’ detection, identification and directional perception ability.

    Place, publisher, year, edition, pages
    Tehran: University of social welfare and rehabilitation sciences Evin, 2009
    Keywords
    Deaf, Deafblind, Directional perception, Environmental sound, Tactile perception
    National Category
    Signal Processing Other Health Sciences
    Research subject
    Electronics; Disability Science
    Identifiers
    urn:nbn:se:oru:diva-8131 (URN)
    Projects
    Sensing the environment
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-10-18Bibliographically approved
  • 8.
    Ranjbar, Parivash
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University, School of Science and Technology.
    Signal Processing Methods for Improvement of Environmental Perception of Persons with Deafblindness2014In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 902, p. 398-404Article in journal (Refereed)
    Abstract [en]

    Environmental perception is a functional area that is severely limited in persons with  deafblindness (DB) who belong a category of people with severe disabilities. Monitor is a vibratory aid developed with the aim to improve environmental perception of persons with DB. The aid consists of a mobile phone with an application connected to a microphone and vibrator. Monitor picks up the sounds produced by events by microphone, processes the sound using an algorithm programmed as an application in the mobile phone and then presents the signal via the vibrator to the persons with DB to be sensed and interpreted. In previous laboratory studies, four algorithms (AM, AMMC, TR, and TRHA) were developed based on modulating, and transposing principles.

    The algorithms were tested by persons with normal hearing/hearing impairment and selected as good candidates to improve vibratory identification of environmental sounds. In this on-going the algorithms are tested by 13 persons with congenital D and five persons with DB using Monitor in a realistic environment, living room, kitchen or office. Forty five recorded environmental sounds were used as test stimuli.

    The subjects tested the algorithms two times, Test and Retest each including a test session

    initiated by a training session. The four algorithms were tested in four days at Test and four days at Retest in total eight test days. Each test day began with a training session where a sound was presented as vibrations to be sensed by the person with the aim to remember its pattern and identity.

    The 45 sounds were grouped in four groups where an specific algorithm was chosen to process an specific sound group in a specific day. At the test session a sound was presented and the person was given 5 randomly chosen sound alternatives to choose the one as represented sound. The algorithms were different for different sound groups during four different test days so all algorithms were used to process all sounds. The algorithms were tested a second time, Retest, in same way as in Test.

    The mean value of identification of environmental sounds varied between 74.6% and 84.0% at Test and between 86.9% and 90.4% at Retest. The identification results at Retest were

    significantly improved (p<0.01) for all algorithms after a relatively short time of training indicating a good learning effect. At Test the algorithm AM was significantly better than the algorithms AMMC and TRHA (p< 0.01) and the algorithm TR was better than TRHA (p<0.01).

    The algorithms AM, AMMC, and TR were selected as good candidates to be implemented in the Monitor to improve environmental perception.

  • 9.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Sinnena, konst och vetenskap: att känna omvärlden2007Conference paper (Other academic)
  • 10.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Vibrotactile identification of signal-processed sounds from environmental events presented by a portable vibrator: a laboratory study2009Manuscript (preprint) (Other academic)
    Abstract [en]

    Objective: To evaluate different signal-processing algorithms for tactile identification of environmental sounds in a monitoring aid for the deafblind.

    Subjects: Two men and three women, sensorineurally deaf or profoundly hearing impaired with experience of vibratory experiments, age 22-36 years.

    Method: A closed set of 45 representative environmental sounds were processed using two transposing (TRHA, TR1/3) and three modulating algorithms (AM, AMFM, AMMC) and presented as tactile stimuli using a portable vibrator in three experiments. The algorithms TRHA, TR1/3, AMFM and AMMC had two alternatives (with and without adaption to vibratory thresholds). In Exp. 1, the sounds were preprocessed and directly fed to the vibrator. In Exp. 2 and 3, the sounds were presented in an acoustic test room, without or with background noise (SNR=+5 dB), and processed in real time.

    Results: In Exp. 1, Algorithm AMFM and AMFM(A) consistently had the lowest identification scores, and were thus excluded in Exp. 2 and 3. TRHA, AM, AMMC, and AMMC(A) showed comparable identification scores (30%-42%) and the addition of noise did not deteriorate the performance.

    Conclusion: Algorithm TRHA, AM, AMMC, and AMMC(A) showed good performance in all three experiments and were robust in noise; they can therefore be used in further testing in real environments.

  • 11.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Science and Technology.
    Akner-Koler, Cheryl
    Örebro University, School of Hospitality, Culinary Arts & Meal Science.
    Konstfack designar hjälpmedel2010In: Audio-nytt, ISSN 0347-6308, Vol. 37, no 4, p. 24-26Article in journal (Other academic)
  • 12.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Science and Technology.
    Anderzén-Carlsson, Agneta
    Örebro University, Department of Health Sciences.
    Neovius, Lennart
    Saven Hitech AB.
    Johansson, Camilla
    Audiologiska forskningscentrum.
    Borg, Erik
    Audiologiska forskningscentrum, USÖ.
    Vibrotactile detection, identification and directional perception of signal-processed sounds from environmental events: a pilot field evaluation in five cases2009In: Iranian Rehabilitation Journal, ISSN 1735-3602, Vol. 6, no 7-8, p. 89-107Article in journal (Refereed)
    Abstract [en]

    Objective: Conducting field tests of a vibrotactile aid for deaf/deafblind persons for detection, identification and directional perception of environmental sounds.

    Method: Five deaf (3F/2M, 22–36 years) individuals tested the aid separately in a home environment (kitchen) and in a traffic environment. Their eyes were blindfolded and they wore a headband and holding a vibrator for sound identification. In the headband, three microphones were mounted and two vibrators for signalling direction of the sound source. The sounds originated from events typical for the home environment and traffic. The subjects were inexperienced (events unknown) and experienced (events known). They identified the events in a home and traffic environment, but perceived sound source direction only in traffic.

    Results: The detection scores were higher than 98% both in the home and in the traffic environment. In the home environment, identification scores varied between 25%-58% when the subjects were inexperienced and between 33%-83% when they were experienced. In traffic, identification scores varied between 20%-40% when the subjects were inexperienced and between 22%-56% when they were experienced. The directional perception scores varied between 30%-60% when inexperienced and between 61%-83% when experienced.

    Conclusion: The vibratory aid consistently improved all participants’ detection, identification and directional perception ability.

  • 13.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Science and Technology.
    Borg, Erik
    Örebro University, School of Health and Medical Sciences.
    Philipson, Lennart
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Auditive identification of signal-processed environmental sounds: monitoring the environment2008In: International Journal of Audiology, ISSN 1499-2027, E-ISSN 1708-8186, Vol. 47, no 12, p. 724-736Article in journal (Refereed)
    Abstract [en]

    The goal of the present study was to compare six transposing signal-processing algorithms based on different principles (Fourier-based and modulation based), and to choose the algorithm that best enables identification of environmental sounds, i.e. improves the ability to monitor events in the surroundings. Ten children (12-15 years) and 10 adults (21-33 years) with normal hearing listened to 45 representative environmental (events) sounds processed using the six algorithms, and identified them in three different listening experiments involving an increasing degree of experience. The sounds were selected based on their importance for normal hearing and deaf-blind subjects. Results showed that the algorithm based on transposition of 1/3 octaves (fixed frequencies) with large bandwidth was better (p<0.015) than algorithms based on modulation. There was also a significant effect of experience (p<0.001). Adults were significantly (p<0.05) better than children for two algorithms. No clear gender difference was observed. It is concluded that the algorithm based on transposition with large bandwidth and fixed frequencies is the most promising for development of hearing aids to monitor environmental sounds.

  • 14.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Borg, Erik
    Örebro University Hospital, Örebro, Sweden.
    Philipson, Lennart
    Örebro University, School of Science and Technology.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Sensing the environment: A perceptual and psychosocial analysis of events in surroundings from a handicapped perspective2003Conference paper (Other academic)
  • 15.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Science and Technology.
    Remes, Johan
    Alexandersson, Linda
    Axelhed, Ingrid
    Timstock hjälper dövblinda uppfatta tiden2010In: AudioNYTT, ISSN 0347-6308, Vol. 37, no 4, p. 28-30Article in journal (Other academic)
  • 16.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Stenström, Ingeborg
    Monitor, a vibrotactile aid for environmental perception: a field evaluation by four people with severe hearing and vision impairment2013In: Scientific World Journal, ISSN 1537-744X, E-ISSN 1537-744X, no Article ID 206734, p. 1-11Article in journal (Refereed)
    Abstract [en]

    Monitor is a portable vibrotactile aid to improve the ability of people with severe hearing impairment or deafblindness to detect, identify, and recognize the direction of sound-producing events. It transforms and adapts sounds to the frequency sensitivity range of the skin. The aid was evaluated in the field. Four females (44-54 years) with Usher Syndrome I (three with tunnel vision and one with only light perception) tested the aid at home and in traffic in three different field studies: without Monitor, with Monitor with an omnidirectional microphone, and with Monitor with a directional microphone. The tests were video-documented, and the two field studies with Monitor were initiated after five weeks of training. The detection scores with omnidirectional and directional microphones were 100% for three participants and above 57% for one, both in their home and traffic environments. In the home environment the identification scores with the omnidirectional microphone were 70%-97% and 58%-95% with the directional microphone. The corresponding values in traffic were 29%-100% and 65%-100%, respectively. Their direction perception was improved to some extent by both microphones. Monitor improved the ability of people with deafblindness to detect, identify, and recognize the direction of events producing sounds.

  • 17.
    Ranjbar, Parivash
    et al.
    Örebro University Hospital. Örebro University, School of Health Sciences. Institutionen för naturvetenskap och teknik, School of Science and Technology.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Akner Koler, Cheryl
    Industrial Design, University Collegeof Arts and Design (Konstfack), Stockholm, Sweden.
    Borg, Erik
    Audiologiskt forskningscentrum i Örebro, Region Örebro län, Örebro, Sweden.
    Identification of vibrotactile morse code on abdomen and wrist2017In: International Journal of Engineering, Technology and Scientific Innovation, ISSN 2456-1851, Vol. 1, no 4, p. 351-366Article in journal (Refereed)
    Abstract [en]

    Morse code has been used as a communications system at a distance to transmit text through tone or light pulses. This comparative study aims to test and evaluate the vibrotactile identification of Morse coded signals communicating instructions for movement. The pulses were presented on abdomen and wrist among 14 males (40-85 yr) experienced in acoustic Morse code and the rate of pulses was 12 words per minute using a Vibration Motor mounted in a plastic holder. There identification results were statistically significantly better on wrist compared to abdomen. Words were identified significantly better on the wrist as compared to abdomen but the identification results of the letters were equally good in both placements. There was a negative correlation between age and the pooled identification results tested on wrist PCC r=-0.45 (p<0.02). The participants rank ordered the wrist, over the abdomen, as the best place for positioning the vibrator. The results support haptic/tactile interaction research in positioning and communication system. Our future plans are to apply the results to the project "Ready Ride" for instructions for horseback riding for people with deafblindness as well as activity and movement for elderly people with impaired vision and hearing.

  • 18.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital, Örebro, Sweden.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Akner-Koler, Cheryl
    University Collage of Arts (Konstfack), Stockholm, Sweden.
    Borg, Erik
    Örebro University Hospital, Örebro, Sweden.
    Haptic Technical Aids for EnvironmentalPerception, Time Perception and Mobility (in a Riding Arena) for Persons with Deafblindness2014In: HAPTICS: NEUROSCIENCE, DEVICES, MODELING, AND APPLICATIONS, PT II, Springer Berlin/Heidelberg, 2014, Vol. 8619, p. 488-490Conference paper (Other academic)
    Abstract [en]

    This demonstration presents three vibrotactile aids to support personswith deafblindness. One aid, Monitor, consists of a microphone that detectssounds from events which are then processed as a signal that is adapted to thesensitivity range of the skin. The signal is sent as vibrations to the user withdeafblindness, who can interpret the pattern of the vibrations in order to identifythe type and position of the event/source that produced the sounds. Another aid,Distime, uses a smart phone app that informs the user with cognitive impairmentand deafblindness about a planned activity through; audio, visual or tactileinteraction that is adapted to the abilities of each individual. The last aid, Ready-ride, uses two smart phones and up to 11 vibrators that help the horse back riderwith deafblindness to communicate with the instructor from a distance viavibrators placed on different parts of the riders body e.g. wrist, thigh, back, ankle.

  • 19.
    Ranjbar, Parivash
    et al.
    Audiological Research Centre, Örebro University Hospital, Örebro, Sweden.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Akner-Koler, Cheryl
    Industridesignprogrammet, Konstfack, Stockholm, Sweden.
    Borg, Erik
    Audiological Research Centre, Örebro University Hospital, Örebro, Sweden.
    Haptic technical aids for improvement of Time perception, Environmental perception and Mobility (in a riding arena) and Music perception for persons with deafblindness2014Conference paper (Refereed)
    Abstract [en]

    Introduction: Persons with deafblindness have frequently difficulties in e.g. environmental perception, spatial awareness, time perception, social participation and music experience. To experience independence, participation and control, adequate processing of sensory information is important.

  • 20.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Science and Technology.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Akner-Koler, Cheryl
    University College of Arts, Crafts and Design in Sweden (Konstfack), Stockholm,Sweden .
    Borg, Erik
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Monitor: a vibrotactile aid to improve environmental perception of persons with severe hearing impairment/deafblindness2012In: TeMA Hörsel, 2012, 2012Conference paper (Other academic)
  • 21.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital. Audiologiskt forskningscentrum i Örebro, Region Örebro Län, Örebro.
    Stranneby, Dag
    Örebro University, School of Science and Technology. Audiologiskt forskningscentrum i Örebro, Region Örebro Län, Örebro.
    Borg, Erik
    Audiologiskt forskningscentrum i Örebro, Region Örebro Län, Örebro.
    Hudens multivibratoriska diskriminationsförmåga för kommunikation med Braille2018Conference paper (Other academic)
  • 22.
    Ranjbar, Parivash
    et al.
    Örebro University Hospital. Örebro University, School of Health Sciences.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Borg, Erik
    Ready-Ride: A tactile communications aid to improve the mobility of persons with deafblindness in a riding arena2018In: International Journal of Engineering Technology and Scientific Innovation, ISSN 2456-1851, Vol. 3, no 1, p. 56-62Article in journal (Other academic)
    Abstract [en]

    Persons with severe visual impairment (VI), blindness (B) and deafblindness (DB) have difficulties in mobility and thereby poor leisure time. Activities as horseback riding become difficult especially for persons with DB who communicate with an assistant/instructor via tactile sign language and need to stop and get information/feedback.

    Ready-Ride, a tactile communications system can improve the mobility of the persons with B and DB by making distance communication possible. It consists of transmitter with four buttons which communicates via Bluetooth with a receiver connected to four vibrators via cables. The button(s) are used to activate the specific vibrator(s). The messages can consist of simple "right" or "left" or more complex codes for any needed instruction.

    Ready-Ride has been evaluated in the riding arena by persons with B and DB who consider it as mobile, easy to use and no need for long introduction or installation of any software/hardware. The vibrations are intuitive, easy to detect and distinguish. The system gives the rider information tactually without disturbing other persons or horses nearby. Using Ready-Ride they got more time to ride and the quality was increased since they could communicate while riding and get immediate feedback directly.

    One of the riders with DB has been using the system during a long period, in average one lesson a week and participated in different competitions with good results. She says that the use of Ready- Ride is crucial for continued riding, "Ready-Ride is a MUST BEE".

  • 23.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Health Sciences. Örebro University Hospital.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Borg, Erik
    Audiologiskt forskningscentrum i Örebro, Region Örebro Län, Örebro.
    Ready-Ride, Ready-Move and VibroBraille Three Tactile Aids to Improve the Mobility of Persons with Deafness, Blindness or Deafblindness2018Conference paper (Other academic)
  • 24.
    Ranjbar, Parivash
    et al.
    Audiological Research Centre, ÖrebroUniversity Hospital, Örebro, Sweden.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Borg, Erik
    Audiological Research Centre University Hospital At Örebro, Örebro, Sweden.
    Akner-Koler, Cheryl
    Theoretical & Applied Aestetics, Industrial Design, University College Of Arts Crafts And Design (Konstfack), Stockholm, Sweden.
    Haptic technical aids Distime, Monitor, Good vibrations, Ready-Ride and VibroBraille for improvement of Time perception, Environmental perception, music perception, mobility and communication for persons with deafblindness: Tactile aids2017In: Tactile aids, Ahlborg, 2017Conference paper (Refereed)
    Abstract [en]

    There are approx. 1300 people with deafblindnes (DB) in Sweden where about 100 of them are with complete deafness (D) and blindness (B). The number will reach about 30000 if we also include people older than 65 with severe visual impairment (VI) and hearing impairment (HI) and several million worldwide.  Difficulties in time perception, environmental perception, music perception, mobility, social participation and communication are examples of their frequent problems. Five haptic technical aids are developed to reduce these problems. Distime is an application in a smart phone to inform the user about the planned activities by choosing different information channel depending on the sense that works and her/his ability. The activities can be presented as sound or vibrations for users with B; as images, movies and also as vibrations for those with D and vibrations for those with DB. Monitor informs users with D and DB about ongoing events with the aim to increase their environmental perception. Using an specific algorithm for environmental sounds, it converts the audible sounds produced by events to sensible vibrations which can be sensed and interpreted as events. Good Vibrations uses an specific algorithm for music and converts the audible music to vibrations which can be felt with the aim to increase music perception for users with severe HI, D/DB as well as for users with normal hearing who want extra enhanced experience of the music. Ready-Ride is a positioning and communication aid to improve the mobility of riders with severe VI, B or DB. It is used for distance communication between a trainer and a rider with VI where the trainer can send information about the rider’s position give commands or feedback about the riding. VibroBraille informs users with B/DB about the short notifications received from different applications in her/his cell phone. It converts the text to its corresponding Braille pattern where the active points are vibrating.

  • 25.
    Ranjbar, Parivash
    et al.
    Örebro University, School of Science and Technology.
    Stranneby, Dag
    Örebro University, School of Science and Technology.
    Erik, Borg
    Audilogiska forskningscentrum.
    Vibrotactile identification of signal-processed sounds from environmental events2009In: Journal of rehabilitation research and development, ISSN 0748-7711, E-ISSN 1938-1352, Vol. 46, no 8, p. 1021-1036Article in journal (Refereed)
    Abstract [en]

    Objective: To compare three different signal-processing principles (eight basic algorithms), transposing, modulating and filtering, and to find the principle(s)/al­go­rithm(s) that result in the best tactile identification of environmental sounds.

    Subjects: Nineteen volunteers (9F/10M), deaf or profoundly hearing impaired, between 18-50 yr. 

    Method: Sounds produced by 45 representative en­vi­ron­men­tal events were processed using the different al­go­rithms and presented to subjects as tactile stimuli using a wide-band stationary vibrator. Eight algorithms based on the three principles (one un­pro­cessed, used as reference) were compared. The subjects iden­ti­fied the sti­mu­li by choo­sing one among ten alter­na­tives drawn from the 45 events. 

    Result and conclusion: Algorithm and subject were significant (RM-ANOVA, p<0.001) factors affecting the results. There were also large differences between individuals regarding which algorithm was best. The test-retest variability was small (Mean±95%CI: 8±3 percentage units), and no correlation between identification score and individual vibratory thresholds was found. One transposing al­go­rithm and two mo­du­lating al­go­rithms led to significantly (p<0.05) better results than did the unprocessed signals. Thus, the two principles of transposing and modulating were appropriate, whereas filtering was unsuccessful. In future work, the two transposing algorithms and the modulating algorithms will be used in tests with a portable vibra­tor for the deafblind.

  • 26.
    Stranneby, Dag
    et al.
    Örebro University, School of Science and Technology.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Akner-Koler, Cheryl
    Örebro University, School of Hospitality, Culinary Arts & Meal Science. University College of Arts, Crafts and Design in Sweden (Konstfack), Stockholm, Sweden.
    Borg, Erik
    Örebro University, School of Science and Technology.
    Ready-Ride: a positioning and communication system to increase the autonomy of riders with visual impairment/deafblindness2012Conference paper (Other academic)
  • 27.
    Stranneby, Dag
    et al.
    Örebro University, School of Science and Technology.
    Ranjbar, Parivash
    Örebro University, School of Science and Technology.
    Montgomery Cederheim, A.
    Audiological Research Centre, Örebro University, Örebro, Sweden.
    RantanenPeterson, M.
    Audiological Research Centre, Örebro University, Örebro, Sweden.
    Akner-Koler, Cheryl
    Audiological Research Centre, Örebro University, Örebro, Sweden.
    Borg, Erik
    Audiological Research Centre, Örebro University, Örebro, Sweden.
    Ready-Ride Increase the Autonomy of Riders with Deafblindness2011Conference paper (Other academic)
1 - 27 of 27
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